This disclosure relates to a variable vane drive system for a gas turbine engine.
A gas turbine engine typically includes a compressor section, a combustor section, and a turbine section. Air entering the compressor section is compressed and delivered into the combustion section where it is mixed with fuel and ignited to generate a high-speed exhaust gas flow. The high-speed exhaust gas flow expands through the turbine section to drive at least the compressor. The compressor section typically includes low and high pressure compressors, and the turbine section includes low and high pressure turbines. Some gas turbine engines include a fan section driven by the turbine section.
Some areas of the engine may include variable vanes. The compressor, for example, may include multiple stages of variable vanes. In some compressor designs, vanes can only be scheduled at first and second positions. The first and second positions are determined by on-ground testing. During flight, the vanes are moved between the first and second positions based on the engine's mode of operation. The vanes may experience wear on primary air-contacting faces in the first and second positions and may need to be replaced if the wear interferes with the engine performance.